1 files changed, 67 insertions, 0 deletions
diff --git a/app/services/git/wiki_push_service/change.rb b/app/services/git/wiki_push_service/change.rb
new file mode 100644
index 00000000000..8685850165a
--- /dev/null
+++ b/app/services/git/wiki_push_service/change.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+module Git
+  class WikiPushService
+    class Change
+      include Gitlab::Utils::StrongMemoize
+
+      # @param [ProjectWiki] wiki
+      # @param [Hash] change - must have keys `:oldrev` and `:newrev`
+      # @param [Gitlab::Git::RawDiffChange] raw_change
+      def initialize(project_wiki, change, raw_change)
+        @wiki, @raw_change, @change = project_wiki, raw_change, change
+      end
+
+      def page
+        strong_memoize(:page) { wiki.find_page(slug, revision) }
+      end
+
+      # See [Gitlab::Git::RawDiffChange#extract_operation] for the
+      # definition of the full range of operation values.
+      def event_action
+        case raw_change.operation
+        when :added
+          Event::CREATED
+        when :deleted
+          Event::DESTROYED
+        else
+          Event::UPDATED
+        end
+      end
+
+      def last_known_slug
+        strip_extension(raw_change.old_path || raw_change.new_path)
+      end
+
+      private
+
+      attr_reader :raw_change, :change, :wiki
+
+      def filename
+        return raw_change.old_path if deleted?
+
+        raw_change.new_path
+      end
+
+      def slug
+        strip_extension(filename)
+      end
+
+      def revision
+        return change[:oldrev] if deleted?
+
+        change[:newrev]
+      end
+
+      def deleted?
+        raw_change.operation == :deleted
+      end
+
+      def strip_extension(filename)
+        return unless filename
+
+        File.basename(filename, File.extname(filename))
+      end
+    end
+  end
+end